You can clone objects:
b = box(pos=vector(1,1,0), axis=vector(1,1,0),
color=color.red)
bcopy = b.clone(pos=vector(1,-1,0))
This will give you two copies of a box, differing only in their positions. After making the clone, changes to the clone do not affect the original box.
If you simply say b.clone(), all of the properties of the new object are exactly the same as those of the original object.
Current restrictions
Currently you cannot clone triangles/quads, because it is the underlying vertex objects that control their appearance. You can clone compound objects.
It used to be the case that there was no way to clone an object from one canvas to another, but now this can be done simply by specifying the other canvas in the arguments to the clone() function, like this: bcopy = b.clone(pos=vector(1,-1,0), canvas=othercanvas).. It is however the case that you cannot clone a compound object to a different canvas; this restriction also applies to extrusion objects, which are compunds of triangles and quads.